Scales of justice fallacy

From Lesswrongwiki

Lady Justice is widely depicted as carrying a scales. A scales has the property that whatever pulls one side down, pushes the other side up. This makes things very convenient and easy to track. It's also usually a gross distortion.

In human discourse there is a natural tendency to treat discussion as a form of combat, an extension of war, a sport; and in sports you only need to keep track of how many points have been scored by each team. There are only two sides, and every point scored against one side, is a point in favor of the other. Everyone in the audience keeps a mental running count of how many points each speaker scores against the other. At the end of the debate, the speaker who has scored more points is, obviously, the winner; so everything he says must be true, and everything the loser says must be wrong.

The scales of justice fallacy refers to the error of using a simple polarized scheme for deciding a complex issue: each piece of evidence about the question is individually categorized as supporting exactly one of the two opposing positions. This scheme distorts the conclusions that can be drawn from each piece of evidence, doesn't allow to take into account the dependencies between the pieces of evidence in the context of the issue, and biases perception of individual pieces of evidence, making the ones that fall into the same category seem to support each other, and ones falling in the opposite categories to seem to oppose each other. In reality, individual pieces of evidence may be separate factual claims, arrived at independently, with the issue depending on specific combinations of facts.